Younger Dryas

During the second half of the Upper Paleolithic, Europe seems to have been divided in two vast
techno-cultural entities with their particular chronological sequence: the Western Europe “classical
sequence” and the Epigravettian sequence in the South. Essentially because of an imbalance of data
and differences in methodologies between these two regions, their Upper Paleolithic sequences have
rarely been compared. Thanks to the development of lithic technology in Europe and a recent active
research about the Late-Glacial, it is today possible to attempt such a challenging exercise of
comparing these two long sequences. In this paper, we solely focus on the Late Glacial. If the rare
existing attempts of comparison focused on typology of lithic assemblages, our paper aims for a more
global approach of lithic industries, based on recent technological studies. This approach allows
highlighting key elements in term of human behaviors. Our data suggest a similar process of change
between Western Europe and the Epigravettian during GI-1 (BøllingeAllerød). All the criteria of the
so called “azilianization process” are actually present in the Epigravettian evolution sequence. This
similar trend within both evolution sequences stopped abruptly, during the GS-1 (Younger Dryas).
During this period and the very beginning of the Holocene (Preboreal), a massive return of blades and
bladelets with high qualitative standards occurred in Western Europe while the simplification process
is still in course in the Epigravettian region. In this paper, we attempt to compare the various
responses of vegetation to the major climatic instability of the Late Glacial across Europe using a
critical survey of the available environmental data. Considering the boundary that could have represented
the Alps between Epigravettian and the Western Europe sequence, two high-resolution
environmental sequences from north and south of the Alps are especially examined. Are the differences
in terms of environmental changes between these two areas significant? Did they play a role in
human behaviors and motivate technological changes? The comparison of palaeoenvironmental data
with archaeological results tends to comfort some hypothesis of environmental determinism proposed
by scholars, but also provide new elements moderating regional models that cannot really be
applied at a continental scale. Climatic correlations with socioeconomic changes highlighted in this
paper are no more than one possible way of investigation that will need to be tested and discussed in
further research.

This paper summarizes current evidence for earliest human occupation of northeastern North America during the late Pleistocene and early Holocene. We review evolution of the region's landscapes and evidence of archaeological chronologies as context for understanding human settlement of the region. Current data support limited evidence for pre-Clovis occupation south of the Laurentide glacial margin, followed by a significant temporal gap prior to early Paleoindian settlement of the region. Despite differences in sub-regional data sets, mapping of site distributions and assemblage data do support the notion of variation in lifeways between Paleoindian populations occupying formerly glaciated parts of the Northeast in the late Pleistocene, versus contemporary groups in lands south of the Laurentide glacial margin. Through time, the greatest differences in Paleoindian land use and technology occur between the Younger Dryas and early Holocene.

This paper examines environmental and archaeological data for the Younger Dryas (YD) (12,900–11,600 calibrated years before present) (cal BP) and early Holocene (11,600–10,000 cal BP) in the New England-Maritimes (NEM) to model environmental changes and possible human responses. For some other regions of North America, researchers argue for negligible environmental changes and human responses, while others suggest that ecological changes associated with cold conditions at the YD onset disrupted regional biota, causing subsistence stress for Paleoindian populations and the end of the Clovis cultural adaptation (circa 13,200–12,900 cal BP). The NEM shows abrupt cooling at the YD onset, which fostered more open habitats favorable to both long-distance migrating and local herds of caribou, and may have encouraged early Paleoindian colonization and settlement of this unoccupied deglacial region. Comparison of the Paleoindian point sequence with calibrated radiocarbon dates indicates fluted point groups probably occupied the NEM during, but not after, the YD. Abrupt warming at the YD terminus (circa 11,600 cal BP) caused a rapid reorganization of the region’s vegetation and prey species populations, coinciding in the archaeological record with a decline in Paleoindian biface fluting technology and altered regional site distributions. In the closed forests of the succeeding early Holocene NEM, late Paleoindian groups (11,600–10,000 cal BP) used unfluted, lanceolate points that may signal post-YD immigration to the NEM.

Research into the earliest occupations in the southeastern United States has been underway since the 1930s,
when a pattern of large-scale excavations combined with the reporting of surface finds was initiated that
continues to this day. Work at Macon Plateau and Parrish Village, excavated during the New Deal, was
followed by a series of stratigraphic excavations in floodplains, rockshelters, and other locales from the 1940s
onward. These early studies produced a basic cultural sequence, portions of which were defined by crossdating
findings from the Southeast with discoveries made in other parts of the country. The Southeast is
unique in that surveys of fluted projectile points have been conducted in every state, some since the 1940s.
These surveys now encompass a wider range of projectile points and other tool forms, and the large
numbers of Paleoindian artifacts found in the region suggest intensive occupation. Whether these quantities
reflect the presence of large numbers of early people, or of modern collectors and extensive agriculture,
remains the subject of appreciable debate. The regional radiocarbon record is fairly robust for the latter end
of the period, but far more sample collection, analysis, and interpretation is needed. The regional literature is
burgeoning, with research being conducted in every state, much of it funded by CRM activity

An enduring problem in North American archaeology concerns the nature of the transition between the Clovis and Folsom Paleoindian complexes in the West. Traditional models indicate a temporal hiatus between the two complexes implying that Folsom was a population replacement for Clovis. Alternatively, if Folsom was an innovation that occurred within Clovis populations and subsequently spread, we would expect to see a temporal overlap. Here, we test these hypotheses using high-quality radiocarbon dates and Bayesian statistics to infer the temporal boundaries of the complexes. We show that the Folsom complex initially appears between 12,900 and 12,740 cal BP, whereas Clovis disappears between 12,720 and12,490 cal BP. Therefore, Folsom may have appeared about 200 years before Clovis disappeared, and so the two complexes likely co-occurred in the West for nearly eight generations. This finding suggests that Folsom was a successful adaptive innovation that diffused through the western Clovis population, eventually going to fixation over multiple generations.

Current Archaeological Research on Paleoindian Sites in Central New York

Jonathan C. Lothrop, New York State Museum
Michael Beardsley, Beauchamp chapter, NYSAA
Mark Clymer, Beauchamp chapter, NYSAA
Susan Winchell-Sweeney, New York State Museum
Meredith H. Younge, New York State Museum

In: Oneida Basin, Glacial Lake Iroquois and Archaeological Contexts, edited and compiled by Eugene Domack, pp. 1-33.  Guidebook for 79th Annual Reunion of the Northeastern Friends of the Pleistocene Field Conference, June 3-5, 2016, Verona, New York (http://www2.newpaltz.edu/fop/).

The Younger Dryas impact hypothesis posits that a cosmic impact across much of the Northern Hemisphere deposited the Younger Dryas boundary (YDB) layer, containing peak abundances in a variable assemblage of proxies, including magnetic and glassy impact-related spherules, high temperature minerals and melt glass, nanodiamonds, carbon spherules, aciniform carbon, platinum, and osmium. Bayesian chronological modeling was applied to 354 dates from 23 stratigraphic sections in 12 countries on four continents to establish a modeled YDB age range for this event of
12,835–12,735 Cal B.P. at 95% probability. This range overlaps that of a peak in extraterrestrial platinum in the Greenland Ice Sheet and of the earliest age of the Younger Dryas climate episode in six proxy records, suggesting a causal connection between the YDB impact event and the Younger Dryas. Two statistical tests indicate that both modeled and unmodeled ages in the 30 records are consistent with synchronous deposition of the YDB layer within the limits of dating uncertainty (∼100 y). The widespread distribution of the YDB layer suggests that it may serve as a datum layer.